酷暑だった夏もいつの間にか終わり、……(中略)……TeX 言語における「展開」に関する正しい理解は不可欠である。
というわけで、コレ。
この問題が悩まずにサラッと解けるようであれば、実用の TeX プログラミングについては十分な「展開力」を持っていると思っていいだろう。
解答集
この問題を Twitter 上で公開したところ、大勢(約 2 名)の人からの解答が得られた。
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マニアにはたまらないコードだね!
(コレはアレだ、という人は、もっと平凡な解答を自分で考えてみよう!)
(続く)